JP2008163783A - EGR cooler with air vent structure - Google Patents

Abstract

An object of the present invention is to provide an EGR cooler having an air vent structure in which an air vent member is disposed in an EGR cooler body and does not interfere with external parts.
Both ends of a plurality of gas side tubes serving as EGR gas passages are held inside the shell by a plurality of partition plates and are supported with a space between the gas side tubes. A tube assembly that partitions the inside and allows the cooling water to pass through the outer surface side of the gas side tube, and cools from the outer surface of the gas side tube with the cooling water flowing into the shell so as to lower the temperature of the EGR gas. In the EGR cooler, an opening of one end of the air bleeding member is provided at the top of the gas phase portion generated inside the tube assembly provided inside the shell, and the other end of the air bleeding member is provided in the cooling water outlet pipe. The gas accumulated in the gas phase part in the shell is discharged to the cooling water outlet pipe side through the air vent member.
[Selection] Figure 1

Description

  The present invention relates to an EGR cooler having an air vent structure in which gas accumulated in an upper portion of cooling water passing through a shell of a main body can be discharged from a cooling water outlet channel.

Conventionally, as shown in FIG. 6, the air vent structure of the EGR cooler has a hole formed in the surface of the shell 2 of the EGR cooler main body (hereinafter simply referred to as the main body) 1 and the pipe connecting member 11a is fixed to the hole forming position. The air bleeding tube 11 was joined. A water outlet pipe 3 and a water inlet pipe 4 are connected to the shell 2, and an air vent pipe 11 is connected to a position higher than the water outlet pipe 3 and the water inlet pipe 4 (Patent Documents 1, 2, and 5). 3).
The air release structure of the EGR cooler having such a configuration makes it possible to discharge air at the time of initial water injection and to quickly discharge steam when the cooling water boils.

JP 2000-274990 A Japanese Patent Laid-Open No. 2001-221593 JP 2005-036765 A

[Problems of the prior art]
In the EGR cooler having such a conventional air vent structure, when the main body 1 is placed horizontally and the main body 1 is mounted obliquely, the air vent member is disposed at the uppermost end portion of the core. Although it is necessary, it is difficult to arrange an air vent member such as a pipe at the upper end, and furthermore, since the air vent member is arranged outside the shell 2 of the main body 1, the engine room is on the engine layout. There is a high possibility of interference with other components in the interior, and particularly when there are many engine layout restrictions such as a small passenger car, the interference often becomes a problem.

  The present invention has been made in view of the above problems in the prior art, and the technical problem specifically set in order to solve this problem is that the air bleeding member is disposed in the EGR cooler body, and An object of the present invention is to provide an EGR cooler having an air vent structure that does not interfere with external parts.

In order to specify an EGR cooler having an air vent structure that effectively solves the above-described problems in the present invention, all the matters recognized as necessary are covered and specifically configured as the problem solving means.
The first problem-solving means related to the EGR cooler having the air venting structure is to hold both ends of a plurality of gas side tubes serving as EGR gas passages by a plurality of partition plates inside the shell forming the EGR cooler. A tube assembly that supports the gas side tubes with a space therebetween and partitions the inside of the shell so that cooling water can be passed to the outer surface side of the gas side tubes is provided inside the shell. In an EGR cooler in which the temperature of the EGR gas is lowered by cooling from the outer surface of the gas side tube with the inflowing cooling water, air is vented to the uppermost portion of the gas phase portion generated inside the tube assembly provided inside the shell. An opening at one end of the member is provided, an opening at the other end of the air bleeding member is provided in the cooling water outlet pipe, and the gas is stored in the gas phase portion in the shell. Tsu gas is characterized in that it has to be discharged to the outlet pipe side of the cooling water through the air vent.

  The second problem-solving means according to the EGR cooler having the air bleeding structure is the same as that described above, wherein the air bleeding member is formed in a pipe shape, a semicircular cross section or a rectangular cross section, and the air bleeding member is formed by brazing or welding. It is characterized by being fixed to the shell and the outlet pipe.

  Further, in the third problem solving means related to the EGR cooler having the air vent structure, the main body of the EGR cooler having the air vent structure is arranged in any one direction of vertical placement, oblique placement, and horizontal placement. It is characterized by that.

  In the first problem solving means related to the EGR cooler having an air vent structure, an opening of one end portion of the air vent member is provided at the uppermost portion of the gas phase portion, and the other end portion of the air vent member is disposed in the outlet pipe of the cooling water. It is possible to discharge the gas accumulated in the gas phase part in the shell to the outlet pipe side of the cooling water through the air vent member, and all the air vent members are inside the EGR cooler. Since it can be accommodated and there is no need to provide an air bleeding member outside the main body, it is possible to avoid interference with other components when mounting the EGR cooler, and to reduce the engine layout constraints.

  In the second problem-solving means related to the EGR cooler having the air vent structure, the air vent member is formed into a pipe shape, a semicircular cross section or a rectangular cross section, and fixed to the shell and the outlet pipe by brazing or welding. Therefore, the air vent structure can be easily formed in the EGR cooler with a simple shape, and it is possible to avoid interference with other parts when installing the EGR cooler, and to reduce the engine layout constraints. Productivity is improved and manufacturing costs can be reduced.

  Moreover, in the 3rd problem-solving means which concerns on the EGR cooler which has an air vent structure, it is more suitable according to the direction which is arrange | positioned by arrange | positioning in any direction of vertical installation, diagonal installation, and horizontal installation. An air vent structure can be formed, productivity can be improved, manufacturing costs can be reduced, and an appropriate EGR cooler can be selected according to the state of use, which can contribute to cost reduction.

Hereinafter, the best embodiment according to the present invention will be described in detail.
However, this embodiment is specifically described for better understanding of the gist of the invention, and does not limit the content of the invention unless otherwise specified.

[First Embodiment]
As shown in FIGS. 1 and 2, the EGR cooler having an air vent structure in the first embodiment is used by placing the main body 1 of a stainless steel EGR cooler vertically.
〔Constitution〕
The main body 1 of the EGR cooler holds a plurality of upper and lower end portions of the gas side tubes 5c,..., 5c serving as EGR gas passages inside the shell 2 by partition plates 5a, 5b at the upper and lower ends. In addition, a tube assembly 5 is provided to partition the inside of the shell 2 so that cooling water can be passed to the outer surface side of the gas side tubes 5c, ..., 5c, and is further sandwiched between partition plates 5a, 5b in the shell 2. A water inlet pipe 4 and a water outlet pipe 3 are connected to the space, and the inflowing cooling water flows through the space formed by the tube assembly 5 to form the liquid phase portion 6 in the main body 1. In the upper part of the part 6 is formed a gas phase part 7 composed of air flowing in at the time of water injection and steam generated at the time of boiling, etc., and the EGR gas flowing in the gas side tubes 5c,. Chu To lower the temperature of the EGR gas is cooled from Bed outside.

  Then, one end portion of the air bleeding member 9 formed by a pipe is disposed on the lower surface side of the upper partition plate 5a, and the other end portion of the air bleeding member 9 is disposed in the outlet pipe 3 of the cooling water. 1. The air release member 9 is fixed to the upper partition plate 5a, the outlet pipe 3 and the like by Ni brazing or welding, and unnecessary gas accumulated on the lower surface side of the upper partition plate 5a in the tube assembly 5 is passed through the air release member 9. The cooling water outlet pipe 3 can be exhausted to the outside.

[Function and effect]
In the main body 1 of the vertical EGR cooler having such an air vent structure, the inside of the tube assembly 5 is a space in which the cooling water is accumulated, and the cooling water flows into the inside of the tube assembly 5 from the water inlet pipe 4 to each gas. The side tubes 5c,..., 5c are cooled, and then flow out from the water outlet pipe 3 to the outside of the shell 2. At this time, the gas is sucked from the gas phase portion 7 through the air vent member 9 due to the negative pressure when the coolant flows out of the water outlet pipe 3, and is sucked from the air vent member 9 into the cooling water of the outlet pipe 3. It is discharged and discharged to the outside together with the cooling water, the water surface of the liquid phase part 6 rises and the gas phase part 7 is eliminated or the gas phase part 7 is reduced to such an extent that the gas side tubes 5c,. be able to.
In addition, since all the air vent members 9 can be accommodated inside the EGR cooler and there is no need to provide the air vent member 9 or other structural members for air vent outside the main body, it interferes with other parts when mounting the EGR cooler. Can be avoided and engine layout constraints can be reduced.

[Second Embodiment]
As shown in FIG. 3, the EGR cooler having the air vent structure in the second embodiment is used by placing the main body 1 of the stainless steel EGR cooler obliquely.
However, the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

〔Constitution〕
The main body 1 of the EGR cooler is held inside the shell 2 at intervals between the end portions of the gas side tubes 5c,..., 5c serving as EGR gas passages by the partition plates 5a, 5b at the end portions. The tube assembly 5 is provided so as to partition the inside of the shell 2 and allow the cooling water to pass through the outer surface side of the gas side tubes 5c, ..., 5c, and is further sandwiched between the partition plates 5a, 5b in the shell 2 A water inlet pipe 4 and a water outlet pipe 3 are connected to the space, and the inflowing cooling water forms a liquid phase portion 6 that flows through the space formed by the tube assembly 5, and water is injected above the liquid phase portion 6. A gas phase portion 7 is formed which is composed of air that sometimes flows in and steam generated at the time of boiling, and the liquid surface maintains a horizontal plane, and the inclination from the vertical line to the body axis and the liquid surface according to the inclination of the main body 1 of the EGR cooler From above The angle to the partition plate 5a is inclined at the same angle, and the temperature of the EGR gas is lowered by cooling the EGR gas flowing into the gas side tubes 5c,. To do.

  Then, one end portion of the air bleeding member 9 made of a pipe is disposed so that the opening end is positioned at the highest position on the lower surface side of the upper partition plate 5a, and the other end portion of the air bleeding member 9 is disposed at the outlet pipe 3 of the cooling water. The gas accumulated in the lower surface side of the upper partition plate 5a in the tube assembly 5 is fixed to the lower surface side of the upper partition plate 5a in the tube assembly 5 from the cooling water outlet pipe 3 through the cooling water outlet pipe 3. Allow exhaust to the outside.

[Function and effect]
In the main body 1 of the obliquely placed EGR cooler having such an air vent structure, the inside of the tube assembly 5 becomes a space through which cooling water flows, and the cooling water flows into the inside of the tube assembly 5 from the water inlet pipe 4 to each gas. The side tubes 5c,..., 5c are cooled, and then flow out from the water outlet pipe 3 to the outside of the shell 2. At this time, the gas is sucked from the gas phase portion 7 through the air vent member 9 due to the negative pressure when the coolant flows out of the water outlet pipe 3, and is sucked from the air vent member 9 into the cooling water of the outlet pipe 3. It is discharged and discharged to the outside together with the cooling water, so that the water surface of the liquid phase part 6 rises and the gas phase part 7 can be eliminated or the gas side tubes 5c,.
In addition, since all the air vent members 9 can be accommodated inside the EGR cooler, there is no need to provide the air vent member 9 or other structural members for air vent outside, and other components are interfered with the mounting of the EGR cooler. Can be avoided and engine layout constraints can be reduced.

[Third Embodiment]
As shown in FIGS. 4 and 5A, the EGR cooler having the air vent structure in the third embodiment is used with the main body 1 of a stainless steel EGR cooler placed sideways.
However, the same members as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof is omitted.

〔Constitution〕
The main body 1 of the EGR cooler holds a plurality of end portions of the gas side tubes 5c,..., 5c serving as EGR gas passages inside the shell 2 by partition plates 5a, 5b at the end portions. In addition, a tube assembly 5 is provided to partition the inside of the shell 2 so that cooling water can be passed to the outer surface side of the gas side tubes 5c, ..., 5c, and is further sandwiched between partition plates 5a, 5b on the shell 2 side. The water inlet pipe 4 and the water outlet pipe 3 are connected to the space, and the inflowing cooling water flows through the space formed by the tube assembly 5 to form the liquid phase portion 6. A gas phase portion 7 composed of air flowing in at the time of water injection and steam generated at the time of boiling is formed, and a liquid level maintaining a horizontal surface is formed at the top of the horizontally placed main body 1, and each gas side tube 5c, ..., 5c The inlet to the EGR gas is cooled from the tube outwardly to lower the temperature of the EGR gas by the liquid phase part 6.

  Then, one end portion of the air bleeding member 9 made of a pipe is disposed so as to open to the uppermost portion of the inner surface in the shell 2 of the main body 1 in which the opening end is placed horizontally, and the outlet of the cooling water is disposed along the inner wall of the shell 2. It arrange | positions to the pipe 3, and arrange | positions the other end part of the air vent member 9 so that an opening end may open in the exit pipe 3 of cooling water, and the air vent member 9 is exited from the shell 2 by Ni brazing or welding. The gas fixed to the pipe 3 and accumulated in the upper part in the shell 2 of the main body 1 placed horizontally via the air vent member 9 can be discharged from the outlet pipe 3 of the cooling water to the outside of the main body 1.

[Function and effect]
In the main body 1 of the horizontal EGR cooler having such an air vent structure, the inside of the tube assembly 5 becomes a space through which the cooling water flows, and the cooling water flows into the tube assembly 5 from the water inlet pipe 4 to each gas. The side tubes 5c,..., 5c are cooled from the outer surface side, and then flow out from the water outlet pipe 3 to the outside of the shell 2. At this time, the gas is sucked from the gas phase portion 7 through the air vent member 9 due to the negative pressure when the coolant flows out of the water outlet pipe 3, and is sucked from the air vent member 9 into the cooling water of the outlet pipe 3. The gas phase part 7 is reduced until the water surface of the liquid phase part 6 rises to eliminate the gas phase part 7 or the gas side tube 5c exposed to the gas phase part 7 disappears. can do.
Moreover, since all the air vent members 9 can be accommodated inside the EGR cooler and there is no need to provide the air vent member 9 or other structural members for air vent outside, the EGR cooler mounting may interfere with other parts. Can be avoided and engine layout constraints can be reduced.

[Another aspect]
Such an embodiment is specifically described in order to facilitate understanding of the gist of the invention, but does not limit the content of the invention, and is not particularly described (including design content). The embodiment is not limited, and may be changed as appropriate. In this sense, some other embodiments that meet the spirit of the invention are shown below.

In the case of a horizontal EGR cooler, as shown in FIG. 5 (B), instead of the pipe-shaped air bleeding member 9, a semicircular or bowl-shaped air bleeding member 10 is joined to the shell 2 by Ni brazing or welding. It may be fixed to the outlet pipe 3. Thereby, the passage of the air bleeding member through which the gas passes can be formed by the portion surrounded by the shell 2, the outlet pipe 3 and the air bleeding member 10.
The opening of the pipe-like air vent member 9 or the semi-circular air vent member 10 disposed in the cooling water outlet pipe 3 may be located at a position where the cooling water flows quickly. There is no need to stipulate the length to be installed inside.
Furthermore, although the EGR cooler which forms a circular tube type heat exchanger was illustrated in the embodiment, even if it is a flat tube type heat exchanger, an air vent structure can be formed similarly.

It is a longitudinal section explanatory view of a vertical EGR cooler having an air vent structure according to the first embodiment of the present invention. It is a partial longitudinal cross-sectional explanatory drawing of the vertical EGR cooler which has an air bleeding structure same as the above, (A) is front sectional explanatory drawing, (B) is side sectional explanatory drawing. It is a partial longitudinal cross-section explanatory drawing of the diagonally-positioned EGR cooler which has the air bleeding structure which concerns on the 2nd embodiment of this invention, (A) is front sectional explanatory drawing, (B) is side sectional explanatory drawing. It is a cross-sectional explanatory drawing of the horizontal EGR cooler which has the air bleeding structure which concerns on the 3rd embodiment of this invention. It is a cross-sectional explanatory drawing of the horizontal installation EGR cooler which has the air vent structure which concerns on 3rd embodiment of this invention, and its modification, (A) is side surface cross-sectional explanatory drawing in case the air vent member of a pipe structure is used (B) is a side cross-sectional explanatory diagram when a semicircular air bleeding member is used. It is an external view which shows the EGR cooler which has the conventional air bleeding structure, (A) is a front view, (B) is a side view.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 (EGR cooler) Main body 2 Shell 3 Water outlet pipe 4 Water inlet pipe 5 Tube assembly 5a, 5b Partition plate 5c Gas side tube 6 Liquid phase part 7 Gas phase part 9 (Pipe-like) air vent member 10 (Semicircular shape) Air release member 11 (conventional) air release member

Claims (3)

In the inside of the shell forming the EGR cooler, both ends of a plurality of gas side tubes serving as EGR gas passages are supported by a plurality of partition plates and are supported with a space between the gas side tubes, and A tube assembly for partitioning the inside of the shell and allowing cooling water to pass through the outer surface side of the gas side tube is provided, and the EGR gas is cooled from the outer surface of the gas side tube by the cooling water flowing into the shell. In the EGR cooler designed to lower the temperature of
An opening at one end of the air bleeding member is provided at the uppermost portion of the gas phase portion generated inside the tube assembly provided inside the shell,
An opening at the other end of the air vent member is provided in the cooling water outlet pipe,
An EGR cooler having an air vent structure, wherein gas accumulated in a gas phase portion in the shell is discharged to the outlet pipe side of the cooling water through the air vent member.   2. The air bleed member is formed in a pipe shape, a semicircular cross section or a rectangular cross section, and the air bleed member is fixed to the shell and the outlet pipe by brazing or welding. EGR cooler having an air bleeding structure.   The main body of the EGR cooler having the air bleed structure is arranged in any one of a vertical position, an oblique position, and a horizontal position. The air bleed structure according to claim 1 or 2, EGR cooler.

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